Various limb prosthesis and orthotic devices have been designed that require a harness system for their operation. However, the benefits of prostheses and orthotic devices are diminished by the harness system in that it can cause user discomfort, reduced cosmesis due to pulling on clothing, and in the case of upper limb prostheses or orthotic devices, poor posturing of the shoulders, shoulder muscle asymmetry, and perceived pain in the contralateral shoulder, arm, and hand due, e.g., to impingement of axillae. Further, the function of a prosthetic or orthotic device with a harness system is often limited in that contralateral body power is needed to operate a terminal device affixed to the prosthetic or orthotic device.